The present invention relates to a terminal unit and a control method for an IC card which is capable of reading various trading data and data regarding an amount of money from the IC card serving as a credit card or as electronic money and a control method therefor.
IC cards are used to serve as portable storage mediums each comprising a nonvolatile memory and an IC chip for controlling the nonvolatile memory.
When an IC card of the foregoing type is used as a credit card or electronic money, it is a convenient fact that various trading data or data about an amount of money can be read by a user of the IC card as necessary.
To meet the above-mentioned requirement, a portable terminal unit for an IC card (including a desktop type terminal unit, as well as the portable type terminal unit) is known which permits a user to always carry the terminal unit. The foregoing terminal unit is formed into a card-like shape similar to the IC card and comprising a keyboard, a liquid crystal display section and a battery. When an IC card is inserted into the terminal unit, various trading data or data about an amount of money is read from the IC card in response to the operation of the keyboard. Then, the terminal unit displays read data on the liquid crystal display section thereof.
IC cards include IC cards of a type comprising a CPU and having a structure adapted to an asynchronous protocol so that data is transmitted in response to supply of a clock and a command from outside. Moreover, the IC cards include IC cards of a type having no CPU and arranged in such a manner as to serially transmit data in synchronization with supply of a clock signal from outside.
A process for reading data from the IC card adapted to the asynchronous protocol and that from the IC card adapted to the synchronous protocol are different from each other. Therefore, there arises a problem in that plural types of terminal units for IC cards must be prepared to be adaptable to the above-mentioned types of the protocols.